This invention relates to a fertility analyzer.
Analyzing mobility and number of spermatozoa is of importance in order to judge the spermatozoa fertility features. Most often nowadays video registration of the spermatozoa movements is used together with computer based analyzing of individual trajectories.
According to a known method, discussed in U.S. Pat. No. 4,601,578, a sperm sample is illuminated by a laser beam and a spectral analysis is made of the laser light scattered from the sample. The signal is transferred through filters and integrators and an output pulse is given each time an integrator is saturated. The saturation pulses are counted. The sample is illuminated by an approximately collimated laser light. The light scattered from the sample is transferred to a detector through a semicircular aperture in a disc and a focusing lens. By this known method only an unspecified sperm motility is detected just to give a general idea of the percentage living sperms in a sample.
However, the fertility is determined by a lot of different features of the spermatozoa, of which the most essential are the translational speed and the rotational frequency, and a quite specific sperm motility value is the ratio between the translational speed and the rotational frequency.
A few years ago a new method was developed by a team in which the inventor of this invention was a participant. According to that method the spermatozoa mobility is measured by analyzing light, which is scattered or emitted when the spermatozoa are illuminated with a laser beam. This method is described in the articles "Rotational and Translational Swimming of Human Spermatozoa: A Dynamic Laser Light Scattering Study", by Rigler, R. & Thyberg, P., Cytometry 5:327-332 (1984) and "Translational and Rotational Swimming of Human Spermatozoa: Maxwell Speed Distribution in the Analysis of Dynamic Laser Light Scattering", by Rigler, R. & Thyberg, P., In "Laser", ed G. Galetti, p. 105, Monduzzi Editore. Bologna (1986). According to these articles, the disclosure of which is incorporated herein by reference and which are attached to the specification as an APPENDIX, the mobility of the spermatozoa gives rise to fluctuations of the scattered light with a frequency related to the translational speed and the rotational frequency of the spermatozoa. The translational speed (in .mu.m/sec) and the rotational frequency (in Hz) for an extensive population of spermatozoa are determined by computer aided Fourier transform analysis of the fluctuation spectrum of the spermatozoa using the light emitted in two directions from a spermatozoa sample illuminated by a laser beam.
The experimental set-up for the measurement of polarized and depolarized dynamic laser light scattering at various angles in a plane perpendicular to the extension of a tube containing the spermatozoa sample shown in the articles mentioned above has not been adapted for clinical analyses. The experimental set-up shown in FIG. 1 in the articles includes an analysing arrangement including many components, and the whole arrangement is moved along a circular path around the sample. The arrangement is thus quite clumsy including heavy parts to be moved.
Therefore, the main object of the invention is to provide an apparatus based on the theories described in the articles but adapted to be a complete instrument easy to handle.